Improvement in pneumatic water-supply systems for buildings



2Sheets-Sheet 1-.

w. E. PRALL. PNEUMATIC WATER/SUPPLY SYSTEM FOR BUILDINGS. N o'.1'7'2', 488. Patented Jan 18, 1876.

N. PETERS. PHOTO LITHOGRAFHER \VASHKNGYON, D. C4

UNITED STATES- WILLIAM E. PRALL, on WASHINGTON, D. 0.,ASSIGNOR o PRALL RAILWAY PATENT OFFICE.

SIGNAL AND TELEGRAPH COMPANY, OF NEW YORK, N. Y.

IMPROVEMENT IN PNEUMATIC WATER-SUPPLY SYSTEMS BUILDINGS.

Specification forming part of Letters Patent No. 172,488, dated January 18 1876; application filed November 21, 1874.

CASE E.

To all whom it may concern:

Be it known that 1, WILLIAM E. PRALL, of Washington city, in the District of Columbia, have invented an Improved Pneumatic Water- Supply System for Buildings, of which the following is a specification: I

My invention relates to an improved method of supplying public and private buildings,

fountains, &c., with water out of'wells, cis terns, or local reservoirs by pneumatic pressare derived from mains or reservoirs charged with compressed air by suitable machinery. It consists of a novel combination and arrangement of one or more water-reservoirs with an air-supply pipe, an automatic prcssere-regulator, and a system of distributingpipes extending from the reservoirs into and about the building to be supplied therefrom. In the accompanying drawings, Figure l is a sectional view illustrating my invention as applied to the water-supply of a building; and Fig. 2 a similar view of an improved form of pressure-regulator to be used therewith.

A, Fig. 1, is an air-tighttank of suitable size to be immersed in the well, cistern, or stream from which a supply of water is. to be drawn. B is a valve arranged at or near the bottom of the tank'to open inwardly, so that the water may readily and naturally flow into the tank by gravitation, and thus automatically refill the same when emptied. G is a discharge-pipe opening into the tank at or near the bottom thereof, and extending thence to the house and grounds, if required. This pipe is fitted with a check-valve,'\V, and may be divided above the valve into two branches, 0 and G the communication be ween the-main. pipe 0 and said branches bei gcontrolled .by means of athre'e waycock, D, whereby- .the communication with one branch" is eut oil when opened with the other, and vice versa. One of these branch pipes, t) is carried directly to all 'points'where a high pressure of water may. be required for use in case of firfia, 8:0. The second branch, C, is used as t e ordinary service-pipe, and connects with the cooks and hydrants commonly used about the house, and in which a high pressure or head of water is 'not required. E is a pipe connecting the water-tank A directly with a reservoir or main pipe kept. constantly charged with compressed air at a high pressure;-and F is an exhaust vent or opening in said-pipe E, which is closed by a three-way cock so arranged as that when the admission of air to the tank from the pipe E is out 01f, communication will be established between the tank and the open exhaust-vent to allow the air in the tank to escape as it is displaced by the j water entering it. G is the. outer casing of an improved automatic, pressureregulator, which is constructed as hereinafter described; and H I are air-pipes connecting the same with the tank A. K is a second cockplaced in the pipe E to cut off at pleasure the direct admission of air to the tank through said pipe, and

that with the high-pressure pipe G be opened 'when the cock K is opened, and vice versa. V

The pressureregulator G (see Fig. 2,) consists of a conical piece, M, playing loosely within a conical chamber inelosed by the easing G, and confined by diaphragms P P, of .rubber or other flexible yielding air-proof material. This loose piece M is so interposed between the diaphragms P and P in contact with both as to transmit .the movement of the one to the other.

trally-perforated piece, "0 or 0 which is screwed down or otherwise, fastened upon the edges of the diaphragm against or upon anoffset or shoulder formed about the opening covered by the diaphragm, so as to fasten the latter with an air-tight joint. E is a port in the casing G, to which the main sair pipe E is 9 connected- This port is formed opposite the minor diaphragm P, which covers the smaller opening into the central diii'erential'chamber of the device.v A valve, N is arranged to open and close the .port E, as shown in Fig. 2, its stem N! beih g extended far enough to bear These diaphragms arese- .cured inplace each by means of a ring or cenagainst the minor diaphragm I", so that an outward movement thereof shall operate to close the valve. The valve is guided in its inoveme its by means of an annular pertorated bearing-piece encircling its stem and projecting there"rom, as shown in the drawing. I is a pipe coii ecting the space or chamber between tlu port 15 and minor diaphragm I. with the -itcr-tank A, through which the air admitted from the pipe E by the valve eontrolling the port E is conducted to said tank A.

An iuclosed aii tight chamber, lt,.is formed over the enlarged or major diaphragm P and communication is established between said chamber t and the water-tank A by means of a pipe, H. I

As the ollice of the loose piece N is merely to transmit the. movementol'theone diaphragm to the other, its form is immaterial, provided its ends afford good bearing and support for the diaphragms. It may, in 1'act,be made in separate sections.

An outward vent maybe pierced to communicate with the central difl'ereutial chamber inclosed by the diaphragms, in order to guard against an accumulation of pressure in said chamber by means of a leak of air therewith under pressure.

The automatic operation of the valve controlling the port E in governing and regulating the admission of air, or of any gas or fluid, from the pipe I) to the tank A, and in determining and maintaining a given pressure thereof in said tank, is determined by the relative proportion of the areas of the two ends ot'*the central differential chamber, covered, respectively, by the major and minor diaphragms l" and I. It', for instance, the areas of the two ends rr openings into the differential chamber be in the proportion of two to one, the pressure of the air admitted against the minor diaphragm '1, covering the opening of smaller area, will be overcome, and the diaphragm forced outward to close the valve so soon as the pressure in the chamber It upon the major diaphragm I, covering the opening of larger area, becomes more than on -halt as great. In other words, if the area of the opening covered by the major diaphragm be twice as large as that of the opening covered by the minor diaphragm, and the pressure of air in the pipe E be twenty pounds to the square inch, the valve'will be closed so soon as the pressure in the pipe I and tank A (and, consequently, in the chamber B, because of the connecting-pipe H) shall become equal to ten pounds to the inch, but the valve will instantly open so soon as the pressure in the chamber It become less than. ten pounds, or one-half less than that in" the'pipe, and, consequently, upon the surface of the valve covering its port 1*).

In the operation of my improved .apparatus, as above described, it, when the tank A is filled withwater, the main cock F be opened and the pressing-cock K closed, compressed air will be admittedto the tank A, and such .constant pressure he maintained upon the water therein as shall cause a gentle [low of water at all the cocks and hydrants having connection with the distributing-pipe 0', the degree of pressure being so determined by an adjustment of the pressiire-re ulator G, as described, as that it will produce a proper flow of water without any unnecessary waste of air from excessive pressure. When, however, iii case of tire, or for use in watering a garden, or other extraordinary occasions, a very great quantity of water or high pressure is desired, thefull pressure of air in the main B may be instantly turned on, and, at the same time, the ordinary low-pressure pipes be protected from this great strain, by

simply turning the cock D, whereby the hi' "hi pressure cock K will be opened, and the chi. nectioii of the main water-pipe O bechanged from the ordinary service-pipe U to the highpressure pipe 0.

When the tank A has been emptied of its contents, the three-way cock I must be. turned so as to out 011' the admission ot air from the pipe E, and permit an escape of the air in the tank A through the exhaust-open-.

ing in said cock F, whereupon the tank will antomaticall y fill by an inflow of the water surrounding it, through the valve B.

I contemplate producing an automatic mo 've pendent of the low-pressure tank A and pipes U, and carrying the high-pressure pipe E (llrectly from the cock K to said second ta'i ik', so that when said cock K is opened the high pressure will be exerted in the second tank and its connected pipes only, without cutting off or afiectiug the supply and flow of water from the tank A through the low-pressure service-pipes.

1 contemplate, also, duplicating the tanks and regulators in connection with the cock F,

so that when the supply of air is out 01f from,

one tank to allow it to fill, it shall be turned .into the second,'so that a flow of water shall be produced thcretrom'into the common distributing-pipcs, and vice-versa.

I clin: as my invention- One or more self-filling Water-tanks, A, and a system of delivery-pipes, C 0, connected therewith, when combined with a high-pressure air-supply pipe, E, pressure-regulating device G, low-pressure air'supply pipe 1,. and high-pressuie cut-0E cock, K, substantially as and for the purpose herein set forth.

W. E. PRALL.

Witnesses:

DAVID A. 13mm, WM. E. KNOWLES. 

